LaTeX: Not working inside the user-defined function in LaTeX

[hainingpan]

The spelling checker did not catch any mistake inside a user-defined function in LaTeX defined \newcommand.

Here is a minimal working example.

\documentclass{article}
\newcommand{\anno}[1]{\emph{#1}}
\begin{document}
    ABCDEFG 

    \emph{ABCDEFG}

    \anno{ABCDEFG}    
\end{document}

The result is here

Here, the user-defined function \anno seems not being checked by cSpell at all.